 
 (defn generate-response
     [package new-description output-format new-user-name old-user-name]
-    (let [ccs-description               (read-ccs-description package)
+    (let [ccs-description               (try-to-read-ccs-description package)
           package-descriptions          (read-package-descriptions products/products package)
           products-without-descriptions (get-products-without-descriptions products/products package-descriptions)
           products-with-descriptions    (get-products-with-descriptions products/products package-descriptions)

            (println "***********" package)
            nil)))  ; special value that will be handled later

(defn read-changes-statistic
    "Read number of changes made by all users."
    []

            (println-and-flush "read-ccs-description(): Error accessing database 'css_descriptions.db'!")
            (println-and-flush e)
            nil)))     ; special value that will be handled later

(defn try-to-read-ccs-description
    "Read package CCS description, but only when package is specified."
    [package]
    (if package
        (read-ccs-description package)
        ""))

(defn read-all-descriptions
    "Read all descriptions from a table 'ccs-db' stored in a file 'ccs_descriptions.db'."
